The variable normal (i.e., straight chain) to iso (i.e., branched) index (VNI) hydroformylation process uses a mixture of two phosphite ligands to allow for an adjustable selectivity in the normal:iso aldehyde product mixture. In particular the three component catalyst system uses a transition metal, typically rhodium (Rh), an organopolyphosphite ligand, typically an organobisphosphite ligand (obpl), and an organomonophosphite ligand (ompl) in which the organomonophosphite ligand to rhodium (ompl:Rh) molar ratio is typically maintained in excess of five to 1 (>5:1) and the organobisphosphite ligand to rhodium (obpl:Rh) molar ratio is controlled between 0 and 1:1 to control the N:I over the range which would be obtained based solely on an ompl:Rh molar ratio (typically between 1 and 5) to that obtained for an obpl:Rh molar ratio (typically between 20 and 40 for propylene). The conventional method of controlling N:I is to control the organobisphosphite ligand to rhodium ratio. In particular the method for lowering N:I is to lower the concentration of the organobisphosphite ligand through the natural decomposition of the ligand through oxidation and hydrolysis. The difficulty with this method, however, is that it is slow, i.e., it takes time for the natural decomposition of the organobisphosphite ligand. Increasing the rate of decomposition of the organobisphosphite ligand is known, but this method increases the expense of the process. Of interest is a method for controlling N:I without decomposing the expensive organobisphosphite ligand.